Electric bicycles, also commonly referred to as “e-bikes,” constitute a category of bicycle having an electric power source to propel the vehicle, or alternatively assists with peddling. Such electric bicycles have grown in popularity over the past decade, with rapid growth in both Europe and Asia. In fact, such devices have begun to replace motorcycles and mopeds in larger urban areas. Electric bicycles are commonly classified as bicycles in most countries, rather than motor vehicles, such that they are not subject to the same laws and licensure as traditional motor vehicles.
It is estimated that there are roughly 120 million electric bicycles in China, with sales rapidly expanding in both India and the Netherlands. A recent report estimates one million electric bicycles will be sold this year in Europe alone. That same report shows that 300,000 sales of electronic bicycles within the United States this year, which is double the number sold in 2009.
Electric bicycles essentially include a rechargeable battery, electric motor and some form of control. Such control can be an on-off switch, but is usually an electronic pulse width modulation control. Batteries currently used for electric bicycles include lead acid, NiCd, NiMH and Lithium ion batteries. The electric power train of these systems can be power-on-demand, where the motor is activated by a handle bar mounted throttle, or a pedelec system (also known as electric assist), there the electric motor is regulated by pedaling. Both types of systems have sensors that detect pedaling speed, pedaling force, or both. An electronic controller provides assistance as a function of the sensor inputs, the vehicle speed and the required force. Most controllers also provide for manual adjustment.
There exist several limitations in current electric bicycle design. One initial issue is aerodynamics, as increased drag will require a larger amount of peddling and/or use of the batteries—both of which will result in a smaller range. A second related issue is aesthetics, as most electronic bicycles are bulky and not visually appeasing.
A third (and perhaps the most) important consideration is storage of electric bicycles during non-use. Due to the bulky nature of electric bicycles, they are often larger and more cumbersome compared to traditional bicycles. In addition, the very purpose and design of these bicycles is for use in large urban areas, such that users of these bicycles do not have the luxury of outdoor storage (such as in a garage) and have limited space in their homes (often in high rise buildings). Moreover, as the cost of electric bicycles can be high (as they cost up to several thousand dollars), it is often desirable to store these items in a secure location rather than simply tethering them at street level.
There exist very little art relating to design of an electric bicycle that can be reduced in size and then later stored. One rudimentary example is U.S. Pat. No. 6,623,023 issued on Sep. 23, 2003. The patent teaches a two hinge assembly which folds the bicycle about a single axis. However, the battery is stored along the shaft of the bicycle, which positions weight away from the user proximate the steering column which makes the device both awkward and less receptive during use (especially when turning the vehicle). Moreover, the design suffers from both aesthetic and aerodynamic issues.
Accordingly, there is a need in the art of electric bicycles for an aesthetic and aerodynamic design in order to increase the efficiency and range of the device. The design should further reduce the overall size of the electronic bicycle for storage in a small space. Moreover, the design should not compromise or risk user performance during use, or the agility of the electric bicycle.